Quickstart: Use Azure Cache for Redis with an ASP.NET Core web app

Article
09/29/2024

In this quickstart, you incorporate Azure Cache for Redis into an ASP.NET Core web application that connects to Azure Cache for Redis to store and get data from the cache.

You can use a caching provider in your ASP.NET Core web app. To quickly start using Redis with minimal changes to your existing code, see:

This article describes how to modify the code for a sample app to create a working app that connects to Azure Cache for Redis.

If you want to go straight to the code, see the ASP.NET Core quickstart sample on GitHub.

You can clone the Azure Cache for Redis samples GitHub repository, and then go to the quickstart/aspnet-core directory to view the completed source code for the steps that are described in this article.

The quickstart/aspnet-core directory is also configured as an Azure Developer CLI template. Use the open-source azd tool to streamline provisioning and deployment from a local environment to Azure. Optionally, run the azd up command to automatically provision an Azure Cache for Redis instance, and to configure the local sample app to connect to it:

azd up

Explore the eShop sample

As a next step, you can see a real-world scenario eShop application that demonstrates the ASP.NET Core caching providers: ASP.NET Core eShop by using Redis caching providers.

Features include:

Redis distributed caching
Redis session state provider

Deployment instructions are in the README.md file in the ASP.NET Core quickstart sample on GitHub.

Prerequisites

An Azure subscription. Create one
.NET Core SDK

Create a cache

To create a cache, sign in to the Azure portal and select Create a resource.
On the Get Started page, type Azure Cache for Redis in the search box. Then, select Create.

On the New Redis Cache page, configure the settings for your cache.

Setting	Choose a value	Description
Subscription	Drop down and select your subscription.	The subscription under which to create this new Azure Cache for Redis instance.
Resource group	Drop down and select a resource group, or select Create new and enter a new resource group name.	Name for the resource group in which to create your cache and other resources. By putting all your app resources in one resource group, you can easily manage or delete them together.
DNS name	Enter a unique name.	The cache name must be a string between 1 and 63 characters that contain only numbers, letters, or hyphens. The name must start and end with a number or letter, and can't contain consecutive hyphens. Your cache instance's host name is <DNS name>.redis.cache.windows.net.
Location	Drop down and select a location.	Select a region near other services that use your cache.
Cache SKU	Drop down and select a SKU.	The SKU determines the size, performance, and features parameters that are available for the cache. For more information, see Azure Cache for Redis Overview.
Cache size	Drop down and select a size of your cache	For more information, see Azure Cache for Redis Overview.

Select the Networking tab or select the Networking button at the bottom of the page.
In the Networking tab, select your connectivity method.
Select the Next: Advanced tab or select the Next: Advanced button on the bottom of the page to see the Advanced tab.
Check the box to enable Microsoft Entra Authentication.

Important

For optimal security, Microsoft recommends using Microsoft Entra ID with managed identities to authorize requests against your cache whenever possible. Authorization with Microsoft Entra ID and managed identities provides superior security and ease of use over Shared Key authorization. For more about using managed identities with your caches, see Use Microsoft Entra ID for cache authentication.
Select the Next: Tags tab or select the Next: Tags button at the bottom of the page.
Optionally, in the Tags tab, enter the name and value if you wish to categorize the resource.
Select Review + create. You're taken to the Review + create tab where Azure validates your configuration.
After the green Validation passed message appears, select Create.

It takes a while for a cache to create. You can monitor progress on the Azure Cache for Redis Overview page. When Status shows as Running, the cache is ready to use.

Get the host name

To connect to your Azure Cache for Redis server, the cache client needs the cache's host name and other information. Some clients might refer to the items by using slightly different names. You can get the host name in the Azure portal.

In the Azure portal, go to your cache.
On the service menu, select Overview.
Under Essentials, for Host name, select the Copy icon to copy the host name value. The host name value has the form <DNS name>.redis.cache.chinacloudapi.cn.

Screenshot showing Azure Cache for Redis properties with the host name highlighted.

Add a new Redis user access policy

The identity that accesses Azure Cache for Redis must be assigned a data access policy. For this example, you assign a data access policy to the same Microsoft Entra ID account that you use to sign in to the Azure CLI or Visual Studio.

In the Azure portal, go to your cache.
On the service menu, under Settings, select Data Access Configuration.
On the Data Access Configuration pane, select Add > New Redis User.
On the New Redis User pane, select the Data Contributor policy, and then select Next: Redis Users.
Choose Select Member to open the flyout menu. Search for your user account and select it in the results.
Select Review + assign to assign the policy to the selected user.

Add a local secret for the host name

In your command window, run the following command to store a new secret named RedisHostName. In the code, replace the placeholders, including angle brackets, with your cache name and primary access key:

dotnet user-secrets set RedisHostName "<cache-name>.redis.cache.chinacloudapi.cn"

Connect to the cache by using RedisConnection

The RedisConnection class manages the connection to your cache. The connection is made in this statement in HomeController.cs in the Controllers folder:

_redisConnection = await _redisConnectionFactory;

The RedisConnection.cs file includes the StackExchange.Redis and Azure.Identity namespaces at the top of the file to include essential types to connect to Azure Cache for Redis:

using StackExchange.Redis;
using Azure.Identity;

The RedisConnection class code ensures that there's always a healthy connection to the cache. The connection is managed by the ConnectionMultiplexer instance from StackExchange.Redis. The RedisConnection class re-creates the connection when a connection is lost and can't reconnect automatically.

For more information, see StackExchange.Redis and the code in the StackExchange.Redis GitHub repo.

Verify layout views in the sample

The home page layout for this sample is stored in the _Layout.cshtml file. In the next section, you test the cache by using the controller that you add here.

Open Views\Shared\_Layout.cshtml.

Verify that the following line is in <div class="navbar-header">:

<a class="navbar-brand" asp-area="" asp-controller="Home" asp-action="RedisCache">Azure Cache for Redis Test</a>

Screenshot that shows a welcome page on a webpage.

Show data from the cache

On the home page, select Azure Cache for Redis Test in the navigation bar to see the sample output.

In Solution Explorer, expand the Views folder, and then right-click the Home folder.

Verify that the following code is in the RedisCache.cshtml file:

@{
    ViewBag.Title = "Azure Cache for Redis Test";
}

<h2>@ViewBag.Title.</h2>
<h3>@ViewBag.Message</h3>
<br /><br />
<table border="1" cellpadding="10">
    <tr>
        <th>Command</th>
        <th>Result</th>
    </tr>
    <tr>
        <td>@ViewBag.command1</td>
        <td><pre>@ViewBag.command1Result</pre></td>
    </tr>
    <tr>
        <td>@ViewBag.command2</td>
        <td><pre>@ViewBag.command2Result</pre></td>
    </tr>
    <tr>
        <td>@ViewBag.command3</td>
        <td><pre>@ViewBag.command3Result</pre></td>
    </tr>
    <tr>
        <td>@ViewBag.command4</td>
        <td><pre>@ViewBag.command4Result</pre></td>
    </tr>
    <tr>
        <td>@ViewBag.command5</td>
        <td><pre>@ViewBag.command5Result</pre></td>
    </tr>
</table>

Run the app locally

In a Command Prompt window, build the app by using the following command:
```
dotnet build
```
Run the app by using this command:
```
dotnet run
```
In a web browser, go to https://localhost:5001.
On the webpage navigation bar, select Azure Cache for Redis Test to test cache access.

Screenshot that shows a simple test completed locally.

Clean up resources

If you want to continue to use the resources you created in this article, keep the resource group.

Otherwise, to avoid charges related to the resources, if you're finished using the resources, you can delete the Azure resource group that you created.

Warning

Deleting a resource group is irreversible. When you delete a resource group, all the resources in the resource group are permanently deleted. Make sure that you do not accidentally delete the wrong resource group or resources. If you created the resources inside an existing resource group that has resources you want to keep, you can delete each resource individually instead of deleting the resource group.

Delete a resource group

Sign in to the Azure portal, and then select Resource groups.
Select the resource group to delete.

If there are many resource groups, in Filter for any field, enter the name of the resource group you created to complete this article. In the list of search results, select the resource group.
Select Delete resource group.
In the Delete a resource group pane, enter the name of your resource group to confirm, and then select Delete.

Within a few moments, the resource group and all of its resources are deleted.